Yay!
I would stick there until you’re very comfortable. You’ll end up at level two for quite a long time. It’s not really a difficulty setting in that sense. It’s very well tuned to your level. So even at just the second level you’ll probably find others are carrying you unless you’re rocking green or blue gear.
I didn’t get to the point of completing third level fairly regularly until I’d maxed my character out and was rocking all purples.
4 and 5 really need a good team that communicates from what I’ve seen and heard. So once you’ve maxed a character out the challenge is absolutely still there.
Tips:
The level of weaponry in the shop is based off the max level of the gear you’re using. So don’t try and save money. You’ll earn plenty anyway, and you need to be consistently buying better gear to shuffle the store contents for even higher gear next time.
And if you want people to be nice. Don’t shoot the feckin daemonhost! That fucker will take two of your team mates out completely when provoked. Then you’ll have to fight your way to them further into the level to rescue them.
Every time I hear one the dread kicks in. Not because of the beastie, but because I don’t know if we’ve got another bloody Leroy on the team 😄